The present teachings are predicated upon providing a stent including two or more stent sections that assist in opening lower/distal or peripheral airway passages. Currently, mechanical stenting is primarily performed in upper/proximal airway passages such as trachea and bronchi. These stents are placed within an airway and expand so that an airway is held open and any restriction in an airway is reduced or eliminated. These stents are good at holding open upper airways and increasing flow through upper airways. Endobronchial stenting and endoscopic techniques for palliation of airway obstruction have been used to correct bronchial stenosis. Traditionally, these techniques are evaluated against surgical options when assessing a patient with an airway obstruction.
Current airway stents are relatively large and cannot fit into smaller airway passages such as a third division or a fourth division airway. Further, once these stents are located within an airway it can be challenging to remove these stents from the airway, and the further into an airway the stents are placed the more difficult they become to remove. Some of the stents are made from a mesh or metallic material that may be subjected to reactions with tissue which may result in granulation of tissue over the stent structure. Further this granulation may make retrieval of the stent more difficult. Examples of valves may be found in U.S. Pat. Nos. 7,691,151; 8,021,385; 8,177,805; 8,454,708; 8,603,127; and U.S. Patent Application Publication Nos. 2014/0330308 and 2013/0345737; Http://www.emphysematrial.com/by-valve-procedure, last accessed on Mar. 12, 2015, all of which are incorporated by reference herein in their entirety for all purposes.
It would be valuable to have a stent, particularly an airway stent, that can pass into smaller passageways in order to open or maintain an open passageway. What is needed is a stent that is biocompatible and does not degrade over time while located within a patient. It would be valuable to have a device that is sufficiently small that the device can fit within the lower/distal airways (e.g., a third division or smaller). What is needed is a device where all or a portion of the device inhibits tissue granulation on the device and is easily removable from an airway. It would be desirable to have a device that was longitudinally movable and rotatable to conform to the walls of a tortuous passageway.